In a seemingly unprecedented move, Prime Minister Hun Sen on Wednesday called for an end to pervasive acts of mob justice following the violent beating of a Phnom Penh professor – who happens to be a member of a ruling party working group – and demanded the arrest of more perpetrators in his case.

On March 11, a mob descended on the car of Suy Sareth, an English professor at the University of Cambodia, after he was allegedly involved in a suspected hit-and-run that injured a motorcyclist.

Sareth – who is also a member of a Cambodian People’s Party working group in Kandal’s Koki Thom commune – was beaten, kicked, pummelled with helmets and had large rocks hurled at his head in videos that went viral after the assault.

Three people – Yath Tithya, 21, An Vinty, 21, and An Phally, 31 – have been arrested and charged with intentional violence, but police have not yet detained one of the key instigators of the mob beating, an allegedly former Daun Penh security guard Pheach Kimhak.

During a speech to garment workers in Por Sen Chey district on Wednesday, Hun Sen said such violence must be “condemned strongly”.

“We do not need people to gather to kill people,” he said, adding drivers who fled the scene of a collision must be arrested and sent to court, not chased down, assaulted and killed.

“We need to avoid becoming the anarchic country which has a record of extra-judicial killing,” Hun Sen said. “We will not allow the criminals to commit such an irresponsible act like this.”

While mob justice is common, a public high-level condemnation and actual arrests are exceedingly rare. The last time the premier spoke publicly about mob violence appeared to be his condemnation of a mob attack on two opposition lawmakers outside parliament in 2015.

At least three of the attackers were later revealed to be members of Hun Sen’s own Bodyguard Unit. Prior to that, in 2003, the premier condemned a nationalist crowd’s attack on the Thai Embassy.

However, he does not appear to have spoken publicly on the much more widespread phenomenon of vigilante mobs attacking suspected perpetrators of crimes, and those participating in the violence are rarely brought in by police.

In at least 10 high-profile cases of vigilante mob justice last year, some of which even resulted in the death of the victim, there were no arrests. Less severe cases, meanwhile, crop up in local media on a regular basis.

The last high-profile case of mob justice where arrests were made appears to be over three years ago, in February 2015, when four people were arrested for beating a lost mentally ill man to death in Kampong Speu after mistaking him for a thief.

While the premier on Wednesday suggested it was unclear if Sareth would live or die from his wounds, the professor – who was sent to Vietnam for treatment – was conscious and able to speak again, and thanked people for their support in a video circulated on Facebook.

Phnom Penh Police Chief Chhoun Sovann on Wednesday said that police had identified and planned to arrest a further eight suspects, but he was “too busy” to name them.

Chan Thou, Koki Thom commune chief in Kandal’s Kien Svay district, confirmed Sareth was a member of a Cambodian People’s Party working group in the commune, under Ngor Sovann, a former opposition supporter who had switched allegiances to the ruling party.

“He has been in the working group more than two years,” Thou said, adding the group had donated money to help pay his medical costs.

“He is a good and gentle and outgoing person, and is friendly with people and is not a cold fish,” he said, adding the group was very happy that the government was “paying attention to arrest the perpetrators”.

San Chey, from social accountability NGO ANSA, said that the premier’s call echoed similar demands from the public for the perpetrators of mob violence to be brought to justice.

“I think in principle it is not only government supporters or ruling party supporters, but every Cambodian has to get justice if they are violated,” he said. “It could raise concerns about nepotism with the intervention from the political leader on this case, while on the other cases [he is] silent, however I encourage the intervention from authorities at all levels.”

Additional reporting by Erin Handley